| Author | Message | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1349 Registered: 5-2001 Posted From: 70.101.192.22 Rating: N/A |
Our clutch wouldn't release completely so we pulled it apart in our yard in Kingman. It was a chore, but it had to be done. The front disc had the hub broken away from the friction surface part of the disk. Aside of visible wear between the intermediate plate and the drive blocks on the flywheel, the rest of the clutch didn't seem too bad. I plan on calling Luke at US Coach in the morning, but I would like to find out if there are any good places for parts and advice that are closer, like Phoenix or Las Vegas. If anyone has any ideas why the steel disc in a clutch would break up midway through it's service life, I would like to hear about it. Thanks. Tom Caffrey | ||
| les marston (Les_marston)
Registered Member Username: Les_marston Post Number: 248 Registered: 1-2010 Posted From: 68.151.225.213  Rating: N/A |
Tom If anyone in the Las vegas area can tell you where to get parts it would be Gary at B&B coach. He does structural repair and mods on coaches but has a contact list for coach stuff as long as your arm. great resource | ||
| joe padberg (Joemc7ab)
Registered Member Username: Joemc7ab Post Number: 464 Registered: 6-2004 Posted From: 66.38.159.33 Rating: N/A |
Tom Is it possible that the friction frooze onto your flywheel because the coach sits too long between use? This is a precaution that MCI put in their manual for the mc1-mc3 to partially relieve the presure of the clutch and prevent this from happening. FWIW Joe. | ||
| Mel La Plante (Mel_4104)
Registered Member Username: Mel_4104 Post Number: 147 Registered: 7-2006 Posted From: 173.180.126.136 Rating: N/A |
les, do you have a contact number for B&B coach and is that Gary Mickerson that has the place. thanks mel 4104 | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 1241 Registered: 11-2005 Posted From: 75.121.201.23  Rating: N/A |
I agree with Joe. This is a common problem with some old Ford farm tractors, I keep mine disengaged with a wire tie down. Same thing happens to older GMC trucks, first hand experience with this!! | ||
| Dal Farnworth (Dallas)
Registered Member Username: Dallas Post Number: 317 Registered: 7-2004 Posted From: 72.172.38.200  Rating: N/A |
Interesting. Let me relate a short, (I hope), story. We have a PD4103, it had a nasty, dirty, greasy, rusty engine. I wanted it nice and shiny clean so I could paint it. I bought a nice 3500 psi pressure washer at a local auction house and only had to put $100 into it to make it work right. To digress back to the subject.... I cleaned the engine nicely, all grease, oil, paint, etc. was gone. Unfortunately, I didn't run the engine after this gargantuan task. Let me add, we aren't travelers, we park for a year or two or five at a time without really moving the bus. One day the time came to head for a job that was about 300 miles away. I fired up the bus, transmission in Neutral, .... no problem! Then I thought, "I'll just take it around the campground to see if everything is up to snuff." Wrong! My cleaning had gotten water between the clutch plates and the fly wheel and rusted them together. No matter what I did, I couldn't break them loose. I finally got everything free by using a piece of metal banding they use for strapping lumber on railroad cars, sliding it between the flywheel and the disc while pulling the edge of the disc back with a prybar. This was a two day job by the way. I figured I would have to replace the clutch, but it has been working well ever since then. Good Luck! Rust will getcha every time! See? I told ya I couldn't make a short post... Almost as bad as Gary LaBombard! | ||
| Jack Fids (Jack_fids)
Registered Member Username: Jack_fids Post Number: 384 Registered: 1-2009 Posted From: 69.171.161.209  Rating: N/A |
(insert Mouse Milk Joke #17 here) | ||
| les marston (Les_marston)
Registered Member Username: Les_marston Post Number: 249 Registered: 1-2010 Posted From: 68.151.225.213 Rating: N/A |
Contact info for Gary at B&B coach in Las Vegas is Gary and Sandy Bennett 4350 S. Arville St. #6, Las Vegas, Nevada, 89103 phone 702 873 4415 fax 702 362 8699 info@bbcoach.com Hope it helps | ||
| George Martinez (Foohorse)
Registered Member Username: Foohorse Post Number: 312 Registered: 1-2010 Posted From: 70.149.50.69  Rating: N/A |
did someone mention mouse milk? | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 1202 Registered: 3-2007 Posted From: 71.55.4.4  Rating: N/A |
Yes Gorge, flipper did.!! Gomer | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1437 Registered: 10-2006 Posted From: 64.241.37.140  Rating: N/A |
IF you are going to spring for a new clutch , take off the flywheel and have it ground , and install it with NEW (there one time one pull) bolts to the crank. FF | ||
| Jack Fids (Jack_fids)
Registered Member Username: Jack_fids Post Number: 385 Registered: 1-2009 Posted From: 69.171.161.237 Rating: N/A |
Grade 5 or 8 bolts..? | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 1204 Registered: 3-2007 Posted From: 71.55.4.4 Rating: N/A |
8 Irepeat Grade 8. Also anti-sieze!! Gomer | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1350 Registered: 5-2001 Posted From: 65.73.109.187 Rating: N/A |
Thanks for the tips, guys. We've got everything apart, now, and it turns out that rust wasn't a problem. I credit the dry air here in Kingman for that. If I had a good intermediate plate and a good disc for a splinesaver clutch, I could put it all back together and use it for another 50,000 miles. The flywheel bolts look like grade 8, but the six marks on the heads are actually shallow slots, so I'm not positive about that. I've seen reports that the new type bolts are to be used on 4104s, but I didn't know that there was any reason for that on the 4106s. I'll try to find out if I need them. Thw flywheel plate is out of the flywheel and easily machined. However, the book says that the plate should be machined while bolted to the flywheel, which looks difficult. We're finding out that the maintenance manual and the actual work differ somewhat. The manual does not cover splinesaver discs and it helps to remove both the reverse lever and the clutch arm before removing the transmission. And the last hard to reach bell housing bolt might be better removed from under the electrical compartment. We have no clue why the disc broke up; I suspect a flaw in the metal started a crack which continued untli the hub and the friction area parted company. I'll try to give updates when I have the time. Tom Caffrey | ||
| joe padberg (Joemc7ab)
Registered Member Username: Joemc7ab Post Number: 467 Registered: 6-2004 Posted From: 66.38.159.33 Rating: N/A |
Tom Remove and resurface your complete flywheel, otherwise you are going to end up with a "wobbly" and shorten your clutch life. Fred has wisely suggested replacing the bolts, and I would also strongly advise the scuffplate as well. Part no that Prevost uses for a 8v71 is 51-0041 for the scuffplate and 51-0266 for the eight bolts. Hope this helps. Joe. | ||
| joe padberg (Joemc7ab)
Registered Member Username: Joemc7ab Post Number: 468 Registered: 6-2004 Posted From: 66.38.159.33 Rating: N/A |
Tom While you are at it,now is the time to check your rear main seal. I donot know if typical antisieze is ok to be used, DD specifies International Compound #2 part no 1#5198563 it comes in a 2 1/2 lb can which they call a special lubricant for Cyl headbolts Mainbearing bolts, and flywheel bolts. Not available in small amount, and therefore 10X the price of a typical tube at a jobber. Dont ask how I know!!!!! Joe. | ||
| joe padberg (Joemc7ab)
Registered Member Username: Joemc7ab Post Number: 469 Registered: 6-2004 Posted From: 66.38.159.33 Rating: N/A |
Tom The failure might have been caused by careless instalation of the transmission the last time the clutch was replaced. Something like that happened to me in a former life!!!!!! Joe. | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1351 Registered: 5-2001 Posted From: 65.73.109.187 Rating: N/A |
Hi, Joe. The manual makes it clear that the parts and the whole have to stay in the plane of rotation. We don't seem to have any warpage. The reason that I questioned leaving the plate in the flywheel is that I don't know how they will do the work, since the drive blocks are cast into the flywheel. The rear main seal is fine; I do have some other leaks to deal with. How would a careless installation cause the disc to break up? Thanks. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| Ralph Peters (Ralph7)
Registered Member Username: Ralph7 Post Number: 180 Registered: 3-2004 Posted From: 75.223.170.19 Rating: N/A |
Is this a double disc clutch, if so one disc in backwards. Is there a picture of the assembly on the net? | ||
| joe padberg (Joemc7ab)
Registered Member Username: Joemc7ab Post Number: 470 Registered: 6-2004 Posted From: 66.38.159.33 Rating: N/A |
Tom Way back when, I replaced a clutch on a three ton truck. Back then I didnot have all the fine tools at my disposal that I now have, so instead of having the transmission nicely hanging from a crane to delicately slide it into place where it is supposed to go, I strongarmed it on my Strongarm jack very appropriately so named and got into position and buttened up, only to have to redo it all over again because it failed within a couple of miles. offcourse Km for us guys north of the 49th!!!! So the lesson I learned from that was to respect friction plates and their tenderness. So Tom if I can pass on any Advise it is to becarefull and all should be well. Joe. | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1352 Registered: 5-2001 Posted From: 65.73.109.187 Rating: N/A |
Ralph, that's what I thought at first, but even though I tried switching them around, I couldn't find the interference that would crack the disc. The front disc cracked, and it was marked "flywheel side" and the marked side was facing the flywheel. There is no slinger, so it was not easy to see how the rear disc was facing. The rear disc is fine, no marks showing that it hit anything. The splinesaver hub has an unsplined end, but it was not obvious which way it should be turned. Thanks. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska (Message edited by pvcces on January 30, 2011) | ||
| Ralph Peters (Ralph7)
Registered Member Username: Ralph7 Post Number: 181 Registered: 3-2004 Posted From: 75.223.43.33 Rating: N/A |
Years ago had a Ford truck with a 534cu.in. gas dump truck, broke all the drive ears off the center plate. Driver said he does not dump clutch with engine reving, the clutch disc were ok. Are cremic/button solid(no springs) clutch disc's avaible for buses? But I have seen them destroyed. How is the wear on the splines on the input shaft, also check the pilot bearing/bushing, change if worn. | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1354 Registered: 5-2001 Posted From: 65.73.109.187 Rating: N/A |
Joe, I mean to be careful; I don't want to redo it. Ralph, the wear on the input shaft is not very noticeable. Two others that I have looked at in the last few months have been much worse, but there was no failure. I think that I'll figure it all out; I just haven't gotten that far, yet. Meanwhile, this next week is supposed to be cold. No fun. Thanks. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| larry currier (Larryc)
Registered Member Username: Larryc Post Number: 344 Registered: 2-2007 Posted From: 207.200.116.13 Rating: N/A |
Take those parts down to American Truck Salvage in Phoenix. They are around 28th and Broadway. Ask them if you can buy some used ones from the gear shop guys. Heck, just call them. I'm just guessin this is a standard 14 or larger double disc. Any local commercial clutch and brake shop can fix you up if they will. Most probaly want to sell you the whole thing. If you try the SS hub both ways, it usually will only fit in the housing one way. I think from the damage you described, the center section retainers are torn out and the center plate is spinning with the discs when you disengage. It's supposed to retain flywheel speed all the time. | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1438 Registered: 10-2006 Posted From: 69.19.14.44 Rating: N/A |
Grade 5 or 8 bolts..? Home Depot bolts might work, but the correct one time bolts come from Detroit , unfortuneatly. FF | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1777 Registered: 12-2000 Posted From: 71.195.124.20  Rating: N/A |
Tom - Any update for us?  | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1355 Registered: 5-2001 Posted From: 65.73.110.194 Rating: N/A |
Hi, RJ and all. I was spending some time trying to figure out how to get stung the least on this clutch work and came to the conclusion that I had better order my pieces from Luke at US Coach. I don't need as many parts as I originally thought. There was really only the one casualty; that's the front disc. I had a couple of oil leaks and some stripped bolt holes, so we are getting parts to fix these problems while we are in there. Luke and I came to the conclusion that I could just replace the splinesaver hub and discs with spring dampened standard discs. I'll be replacing the throwout and pilot bearings on GP. I had a talk with Cliff tonight and he said that every time he had a chance to replace the rear main seal and didn't do it, the seal would start leaking, so I guess that I'll get that done, too. For what it's worth, the disk broke several months ago, but the clutch could be disengaged. We took a trip to the Carlsbad Caverns and the Grand Canyon without that front disc holding anything. The clutch only slipped when idling, never on the road. I expect it will be another week before the clutch job is finished. For anybody tackling this job, there are three different clutch configurations to choose from. The book shows three flywheel slots but there are six slot ones (we have one), and the intermediate plate, which has three ears, can go in different slots. The slots we were using are around .030" wider than the other set, so we are going to use the narrower ones. As I get further along, I'll post more info for the board. Take care. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| George M. Todd (George_todd)
Registered Member Username: George_todd Post Number: 1175 Registered: 8-2006 Posted From: 99.146.10.157 Rating: N/A |
Hmmmmm, The cause of the failure couldn't be lugging/chattering due to "dead throttle starts" could it? G | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1778 Registered: 12-2000 Posted From: 71.195.124.20 Rating: N/A |
George - I've ridden with Tom in his coach numerous times. But before I comment about his starting technique, I have a question: Please explain to me exactly what your definition of a "dead throttle start" is. TIA | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1356 Registered: 5-2001 Posted From: 65.73.110.194 Rating: N/A |
I see that George has not been convinced about dead throttle starts, has he? While he raises a legitimate point, I am leaning towards a flaw in the disc steel. The disc broke from hole to hole all the way around the disc. The least worn disc is the one that broke, so I'm not sold on the idea that one disc was doing all the work, which seems to be the idea that Ted Campbell favors. It's hard saying if we will ever know the cause of the disc failure. For what it's worth. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1790 Registered: 12-2000 Posted From: 71.195.124.20 Rating: N/A |
Tom - Do you have an update on the clutch repair? | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1357 Registered: 5-2001 Posted From: 74.33.4.25 Rating: N/A |
Hi, RJ. Yes, I do. We had a flood over the weekend, and I am waiting on a motor mount from Luke to begin reassembly of the clutch and transmission. The coach is setting in mud, so I don't want to disturb it until the ground firms up. The prior mechanic(read the person hired by the prior owner) left one of the bearing retainers with 3 out of 6 bolts broken. I figured that I should fix those before moving on. That took Helicoils and patience to repair the retainer. One other motive for not getting in a hurry to get the clutch finished is that my latest house closed a few days ago, so I went to work on that. The clutch looks like we will get a good repair out of the job. We are going back from splinesaver to spring discs because the wear on the input shaft spline was less than expected. I expect it will be around a week before I get back on it. There, you have it. Tom Caffrey | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1359 Registered: 5-2001 Posted From: 65.73.109.247 Rating: N/A |
Hi, fellow busnuts. The weather gods finally smiled and the new clutch parts are in. The clutch works as it used to, at it's best. One surprise is that climbing up on runup blocks is easier than it used to be. The flywheel bolts are not the same as the Prevost ones; these are only six. Bill at US Coach knew that there were different configurations and asked the right questions to come up with the right ones. One thing that slowed everything down was that the pictures in the maintenance manual did not show the parts that we took out or the ones that we put in. This led to guesswork that might have been avoided if the parts had matched the manual. We used one of those engine hoists that look like a miniature crane; this made it fairly easy to keep from hanging too much weight on the discs. We went back with a new pilot bearing, new crank to flywheel bolts and new spring discs and used the old intermediate plate in the least worn slots. Somewhere along the line, we knocked out both the speedometer and the cruise control. Since they have separate inputs, there were two problems to fix. The speedometer is fixed; the front wheel coil was open and somebody had cut it out of the circuit. There was a sender on the transmission that was good. I was just sure that it had been abandoned; I was wrong. The cruise has still got me guessing. I will go through the troubleshooting in the manual to see if I can fix it. One other thing; vibration was pretty pronounced before we tore the clutch down. I didn't notice any during my test drives. I will know for sure if it is a problem only after some hard pulls. I'll try to give some updates when I've driven the coach enough to know how well it's doing. Also, the two control rods that control the position of the engine are worth looking at. We had two bad mounts and one of the control rods was far enough out of adjustment to cause metal to metal contact between the engine and the cradle. That's about it, for now. Thanks, everyone, for all the help. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1360 Registered: 5-2001 Posted From: 65.73.109.247 Rating: N/A |
Update. The cruise control is operational; there was a broken conductor running past the transmission which was likely broken during the work. The engine vibration is no more, and there is no noise of metal to metal contact at the engine mount. For now, all is well. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska |